Cat Back Exhaust Question

[sloth4urluv]

If I am running AFM/MAF calibration and replace my cat Back exhaust, is retuning with flashpro going to net any noticiable gains? (Header/Cat is stock).

Looking through the calibrations that come with flashpro I do not see any for afermarket cat back exhaust systems.

[Spunkster]

The exhaust system on the SI is pretty good from the factory. There is not much to gain by changing the exhaust.